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arXiv · cond-mat/0609287

Kosterlitz-Thouless behavior in layered superconductors: the role of the vortex-core energy

Abstract

In layered superconductors with small interlayer Josephson coupling vortex-antivortex phase fluctuations characteristic of quasi two-dimensional (2D) Kosterlitz-Thouless (KT) behavior are expected to be observable at some energy scale $T_d$. While in the 2D case $T_d$ is uniquely identified by the KT temperature $T_{KT}$ where the universal value of the superfluid density is reached, we show that in a generic anisotropic 3D system $T_d$ is controlled by the vortex-core energy, and can be significantly larger than the 2D scale $T_{KT}$. These results are discussed in relation to recent experiments in cuprate superconductors, which represent a typical experimental realization of layered anisotropic superconductors.

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L. Benfatto, C. Castellani, T. Giamarchi. 2007-02-16. Kosterlitz-Thouless behavior in layered superconductors: the role of the vortex-core energy. https://doi.org/10.1103/physrevlett.98.117008

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